Hoistway door interlocks are required to prevent an elevator car from being operated by its motive means until the hoistway door at the position of the elevator car is locked in the closed position. The interlock, after the car leaves the position of the hoistway door, then prevents the hoistway door from being opened from the landing side by unauthorized personnel, until the elevator car is again within the landing zone of the floor and is either stopped or being stopped. When the hoistway door moves to the closed position, the hoistway door is mechanically locked, and after the mechanical lock is made, an electrical indication is provided for the elevator drive control which enables the associated motive means to operate the car.
The hoistway door interlock, since it is subject to mechanical and electrical actuation every time the elevator car stops at the associated floor, should be rugged and reliable, it should require no lubrication, and it should have the ability to provide an electrical indication after the hoistway doors are locked even when the electrical components which must cooperate are misaligned. If the electrical indication is not given after the hoistway doors are properly locked, the car will not move away from the floor and elevator service by this car is terminated until service personnel can be called to correct the problem. Thus, it is the object of the present invention to improve the electrical switch which provides the electrical indication after proper mechanical locking of the hoistway door, to strive to achieve the desirable reliable, maintenance-free aspects.